Mike, the OP does not mention "pegging the runner in the back," but instead stipulates INT with a thrown ball. I'm envisioning the BR swiping at F3's glove as he runs past 1B, à la A-Rod.

You're NOT saying you cancel the out on R2 because of the BR's INT at 1B, are you? I'm negating R3's run because he's not likely to have been running on the pitch, and so wouldn't reach HP before the BR reaches 1B (the TOI).

Why wouldn't R2's out count as an intervening play? It's a play, and it intervenes between the batted ball and the INT!

Michael,

In my experience, on a ball batted into play, the R3 will invariably score before the BR reaches 1B.

What I intended to say was that...

If the R3 did in fact reach HP before the interference,

AND

you returned the R3 to 3B as a result of the BR's interference,

you would have to return the "apparently retired" R2 to 2B as well.

As I said, I'm not really sure whether a play at a base other than HP "counts" as an intervening play. In addition to what I said in my previous post, you will notice that greymule included the "...at home plate..." qualifier, and I have seen other credible posters suggest the same thing in the past.

To me, it seems that ANY intervening play should qualify to invoke the "exception" - I'm just not sure. And, I can't find any credible interpretation that clarifies the question one way or the other.

JM

I was under the impression that the intervening play had to be at home plate. Yes, the case plays always have the play there, but I also remember reading some seemingly authoritative interpretation that mentioned the "finality of a run scoring." The same source said that a runner from 2B who had advanced to 3B during the intervening play at home would have to return to 2B even if he had reached 3B before the INT.

But I'm going only by what I drew from the discussion on that thread. I do not know for certain.

Seems to me that the point of the intervening play exception is to determine if a run scores or not.